These guys can eloquently fill you in on the down sides to consolidation, but I would encourage you to spend some time at the library researching the economies of scale and other efficiencies that led to these mergers. Some argue that these efficiencies are needed to keep some stations in operation in challenging economic times, but that is probably overstatement in some cases.
In any event, there are pluses and minuses. Generally minus for the rank and file, more of a mixed bag for executives who may get more opportunities if they survive, but will have to prove they deserve one of the fewer remaining chairs in order to do so.
As far as the audience - there is both a homogenization of product and an ability to share resources (BZ news on ch38, 7 News on 56, Sox on EEI and RKO...), so to some extent that cuts both ways too.
Good luck.